The Himalayan jumping spider becomes brilliant when you realize its natural prey are the green butterflies we see in Meechee’s song, "Wonderful Life".
During the credits, a photo of the pilot Brenda said was suffering from altitude sickness and Gwangi is shown with a filter that shows them both throwing up(albeit colorful and sparkly). One symptom of altitude sickness is vomiting.
'Migo' is a westernization of the Tibetan "Mi-Goh", another name for the Yeti.
The movie shows us where the Yetis get food (some kind of organic geodes) but what about the woolly mammoths they ride on and populate the village? Mammoths were almost exclusively grass-eaters, and the spreading of forests after the last ice age is one of the likely causes for their extinction in real life. Even assuming the Yetis' mammoths are a subspecies that evolved a more generalist herbivore diet, there doesn't seem to be nearly enough plant life on the mountaintop to sustain a whole population of them.